If you are referring to the episode " A Sound Argument " (Season 4, Episode 10), it is a story centered on the heavy burden of duty and the erosion of hope.
Set two years before the present-day conflict, the episode explores the introduction of foreign diplomacy to Paradis Island and the tragic weight placed on Queen Historia. The Visit from Hizuru 10 : A Sound Argument
The story begins with the arrival of Lady Kiyomi Azumabito, the first foreign guest to visit the walls of Paradis. She reveals a hidden lineage: is the lost descendant of the Shogun of Hizuru. While the news brings a glimmer of a possible ally, it comes with a steep price tag: Zeke Yeager’s "Three-Point Plan" for Eldia’s survival. Zeke's Plan and the Sacrifice Zeke’s strategy involves: If you are referring to the episode "
: In a poignant flashback, Eren Jaeger vehemently refuses to let Historia be used as a "breeding tool". She reveals a hidden lineage: is the lost
: A small-scale display of the Wall Titans' power to deter world invasion.
The episode concludes with the realization that while the plan was logically "sound," it destroyed the very humanity the Survey Corps fought to protect. Attack on Titan - Season 4 Episode 10 - "A Sound Argument"
: Paradis must spend 50 years modernizing their military to compete with the world.